giles
62712accdd
Some checks failed
Test, Build, and Deploy / test-build-deploy (push) Failing after 23s
Shoelace formula on a pentagon with integer vertices:
pts = [(0,0); (4,0); (4,3); (2,5); (0,3)]
2 * area = | Σ (x_i * y_{i+1} - x_{i+1} * y_i) |
= | 0*0 - 4*0 + 4*3 - 4*0 + 4*5 - 2*3 + 2*3 - 0*5
+ 0*0 - 0*3 |
= 32
Returns the doubled form (32) to stay integral.
Tests:
- let (x1, y1) = arr.(i) in -- tuple destructure from array
- arr.((i + 1) mod n) -- modular wrap-around index
- if a < 0 then - a else a -- prefix - negation
162 baseline programs total.